Dielectric resonator apparatus having adjustable external structure and method of adjusting same

Abstract

A dielectric resonator apparatus contains coaxial resonators in a dielectric block made of a dielectric material, having a first end surface, a second end surface and a plurality of side surfaces therebetween. The block is formed with resonator-forming throughholes penetrating therethrough and having openings on the first and second end surfaces. Inner conductors are formed inside these resonator-forming throughholes, and an outer conductor is formed at least on the side surfaces and the first end surface. A molded resin member made of a dielectric resin material, having pin-accepting holes therethrough, is attached to the resonator-forming throughholes. Input/output terminals are formed on the molded resin member so as to be insulated from the inner and outer conductors. Metallic pins are inserted into the pin-accepting holes to thereby contact the input-output terminals and to provide external-connection capacitance with the inner conductors. A conductive film is formed at least on the second end surface or the molded resin member for preventing electromagnetic waves from leaking outside. Functional characteristics of such an apparatus can be adjusted by controlling the external-connection capacitance by varying the distance by which the metallic pins are inserted into the pin-accepting holes.

What is claimed is: 
     
       1. A dielectric resonator apparatus containing coaxial resonators; said apparatus comprising: a dielectric block made of a dielectric material, having a first end surface, a second end surface and a plurality of side surfaces between said first and second end surfaces, said block being formed with resonator-forming throughholes penetrating therethrough and having openings on said first and second end surfaces;   inner conductors inside said resonator-forming throughholes, annular insulating sections being provided inside said throughholes to prevent said inner conductors from reaching said second surface;   an outer conductor at least on said side surfaces and said first end surface;   a molded resin member made of a dielectric resin material, having pin-accepting holes therethrough and being attached to said resonator-forming throughholes;   input/output terminals formed on said molded resin member and insulated from said inner conductors and said outer conductor;   metallic pins adapted to be inserted into said pin-accepting holes to thereby contact said input-output terminals and to provide external-connection capacitance with said inner conductors; and   a conductive shielding film formed on said second end surface, said conductive shielding film preventing electromagnetic waves from leaking outside.   
     
     
       2. A method of adjusting functional characteristics of a dielectric resonator apparatus containing coaxial resonators and comprising: a dielectric block made of a dielectric material, having a first end surface, a second end surface and a plurality of side surfaces between said first and second end surfaces, said block being formed with resonator-forming throughholes penetrating therethrough and having openings on said first and second end surfaces;   inner conductors inside said resonator-forming throughholes, annular insulating sections being provided inside said throughholes to prevent said inner conductors from reaching said second surface;   an outer conductor at least on said side surfaces and said first end surface;   a molded resin member made of a dielectric resin material, having pin-accepting holes therethrough and being attached to said resonator-forming throughholes;   input/output terminals formed on said molded resin member and insulated from said inner conductors and said outer conductor;   metallic pins adapted to inserted into said pin-accepting holes to thereby contact said input-output terminals and to provide external-connection capacitance with said inner conductors; and   a conductive shielding film formed on said second end surface, said conductive shielding film preventing electromagnetic waves from leaking outside;   said method comprising the step of controlling said external-connection capacitance by varying the distance by which said metallic pins are inserted into said pin-accepting holes.   
     
     
       3. A dielectric resonator apparatus containing coaxial resonators; said apparatus comprising: a dielectric block made of a dielectric material, having a first end surface, a second surface and a plurality of side surfaces between said first and second end surfaces, said block being formed with resonator-forming throughholes penetrating therethrough and having openings on said first and second end surfaces;   inner conductors inside said resonator-forming throughholes;   an outer conductor at least on said side surfaces and said first end surface;   a molded resin member made of a dielectric resin material having pin-accepting holes therethrough and being attached to said resonator-forming throughholes; input/output terminals formed on said molded resin member and insulated from said inner conductors and said outer conductor;   metallic pins adapted to be inserted into said pin-accepting holes to thereby contact said input-output terminals and to provide external-connection capacitance with said inner conductors; and   a conductive shielding film formed on said molded resin member, said conductive shielding film preventing electromagnetic waves from leaking outside.   
     
     
       4. The dielectric resonator apparatus of claim 3 wherein said dielectric block has resonator coupling means formed therethrough for coupling resonators formed by said inner conductors. 
     
     
       5. A method of adjusting functional characteristics of a dielectric resonator apparatus containing coaxial resonators and comprising: a dielectric block made of a dielectric material, having a first end surface, a second end surface and a plurality of side surfaces between said first and second end surfaces, said block being formed with resonator-forming throughholes penetrating therethrough and having openings on said first and second end surfaces;   inner conductors inside said resonator-forming throughholes;   an outer conductor at least on said side surfaces and said first end surface;   a molded resin member made of a dielectric resin material, having pin-accepting holes therethrough and being attached to said resonator-forming throughholes;   input/output terminals formed on said molded resin member and insulated from said inner conductors and said outer conductor;   metallic pins adapted to be inserted into said pin-accepting holes to thereby contact said input-output terminals and to provide external-connection capacitance with said inner conductors; and   a conductive shielding film formed on said molded resin member, said conductive shielding film preventing electromagnetic waves from leaking outside:   said method comprising the step of controlling said external-connection capacitance by varying the distance by which said metallic pins are inserted into said pin-accepting holes.